import java.util.Scanner;

public class Market {
    public static void main(String[] args) {
        System.out.println("请输入商品的单价");
        Scanner scanner = new Scanner(System.in);
        String price = scanner.nextLine();

        System.out.println("请输入购买商品的数量");
        Scanner scanner1 = new Scanner(System.in);
        String numbers = scanner.nextLine();

        System.out.println("请输入该商品的打折情况：1正常收费,2打八折，3打七折，4打五折");
        Scanner scanner2 = new Scanner(System.in);
        String count = scanner.nextLine();
        switch (count){
            case "1":
                System.out.println("总的价格为:"+Double.valueOf(price)*Double.valueOf(numbers));
                break;
            case "2":
                System.out.println("总的价格为:"+Double.valueOf(price)*Double.valueOf(numbers)*0.8);
                break;
            case "3":
                System.out.println("总的价格为:"+Double.valueOf(price)*Double.valueOf(numbers)*0.7);
                break;
            case "4":
                System.out.println("总的价格为:"+Double.valueOf(price)*Double.valueOf(numbers)*0.5);
                break;
        }
    }
}
